President Barack Obama said the United States will "speak out forcefully" for the freedom of the Cuban people, after announcing a move toward normalizing ties with Cuba and opening an embassy on the communist-led island nation.

In an interview with ABC News, Obama said he told Cuban President Raul Castro in a telephone call Wednesday the U.S. would continue promoting democracy and human rights.

Obama said that he did not expect Castro to suddenly alter his government, but that generational changes inside Cuba are likely to inspire friendlier relations in the future. He also stressed the importance of having a diplomatic presence in Cuba, saying that the U.S. is in a better position to influence one-party states when it has an active ambassador.

Announcing the agreement earlier at the White House, Obama said it was "time for a new approach" with Cuba and that 50 years of isolation "has not worked."

As he spoke, Castro made his own announcement in Havana, saying Obama "deserves respect and recognition from our people."

The two leaders spoke by phone for nearly one hour on Tuesday in what was the first substantive presidential contact between the U.S. and Cuba since 1961.

Gross release

The move also came as Cuba released Alan Gross, the American contractor who was arrested in Havana in 2009 for bringing communications equipment to the island.

He had been sentenced to 15 years in prison. Obama said Gross and a man described as "one of the most important [U.S.] intelligence agents" were exchanged for three Cuban intelligence operatives who spent more than a decade in U.S. prisons.

The diplomatic shift followed more than a year of secret talks between the two longtime ideological foes, with involvement from Canada and Pope Francis. The pontiff voiced his "warm congratulations" on the renewal of diplomatic ties between the countries. United Nations Secretary-General Ban Ki-moon called the news "very positive."

Carter welcomes move

Former U.S. president Jimmy Carter welcomed what he called Obama's "wise and courageous" decision to improve relations with Cuba, and he congratulated Alan Gross and his family on the contractor's release from prison. Carter called on the U.S. Congress to take steps to remove economic sanctions against the Cuban people.

Carter met with Gross back in 2011 in Havana, and called on authorities there to release him.

The United States and Cuba have interests sections that are technically part of the Swiss embassies in each other's capitals. As president, Carter approved the opening of the interests sections.

Business, travel ties

Obama said business and travel ties will be launched, but that he will have to negotiate with the U.S. Congress over ending the country's economic sanctions against Cuba.

After the president's announcement, U.S. House of Representatives Speaker John Boehner said, "Relations with the Castro regime should not be revisited, let alone normalized, until the Cuban people enjoy freedom - and not one second sooner." He added, "There is no ‘new course’ here, only another in a long line of mindless concessions to a dictatorship that brutalizes its people and schemes with our enemies."

Obama said he has "no illusion" that the individual rights of Cubans will improve immediately. But he said when the U.S. disagrees with Cuban actions, it will be able to tell Havana directly.

The White House said the longstanding U.S. policy of attempting to contain and isolate Cuba actually "isolated the United States from regional and international partners [and] constrained our ability to influence outcomes throughout the Western Hemisphere."

The Obama administration's statement said although U.S. policy toward Cuba is "rooted in the best of intentions, it has had little effect. Today, as in 1961, Cuba is governed by the Castros and the Communist Party."